Party-line signaling system.



- V PATENTED JAN. 16, 1906. A. F. POOLE & P. B. HALL.

PARTY LINE SIGNALING SYSTEM.

APPLICATION FILED 0UT.13, 1902.

2 sums-sum 1.

WJUESSES- Q IIEEUL S- EERI- la No. 810,346. I

2 SHEETS-SHEET 2.

PATENTED JAN. 16, 1906. A. F. POOLE & F. B. HALL.

, PARTY LINE SIGNALING SYSTEM.

APPLICATION IILED 00T.13,1902.

- and FRANK B. 1 States, residing at Wheeling,

UNITED sTArns PATENT OFFICE.

ARTHUR F. POOLE AND FRANK 1;.- HALL, or

WHEELIN G, WVEST VIRGINIA. PARTY- LINE' SIGNALING srfs'rzm- Specification of Letters Patent.

PatentedJ'an. 16, 1906.

Application filed October 13,1902, Serial No- 127,114.-

- and-exact description, reference being had to stalled at each of the g party-line such that currents, passing over a which are adapted to send a number of imthe inclusion of the subscribers telephone in Our invention relates to ing systems, such as are frequently employed through that substation.-

- through the building-up the accompanying'drawings, forming a part of this specification.

party-line signalfor use in connection with selective partyline telephone systems. a

We disclose herein a selective party-line telephone system employing two metallic lines, one of which may be looped in to form a series connection at all or any desired number of substations upon a party-line. The other of the two metalliclinesis preferably provided with a parallel or brid e connection with each of the substations. n connection with this system we find it desirable to employ a ground return-circuit, which acts in conjunction with the wire. Selective apparatus is desirably insubstations upon the circuit formed by the'serie's wire to any given substation and thence through the ground tothe central station will build up the loop-line of the loop-line will be accomplished no matter in which direction the currents pass circuit; but the selective apparatus located at each of the substations is further provided with other instrumentalities such that when the selective currents mal direction only the building up of the line is accomplished, while when the currents pass inthe opposite direction this line is not only built up, but a subscribers signaling instrument, such as a telephone, is also-thrown into bridge connection across the telephonelines. Thusin order to build up the partyline and to connect any desired substation with the metallic line itis necessary to provide at the central station instrumentalities pulses over the building-m) circuit correspondmg to the number of substations lo cated upon any party-line, any desired numloop or series metallic This building up pass in what may be termed the norscribers.

ber of which current impulses may be reversed in d1rect1on,'so as to connect in the telephone instruments at such substations as may be desired. In the selective apparatus employed the mechanism which builds up the loop-line also serves to disconnect the ground return-circuit, so that no further currents may flow through the setting-up circuit without first restoring the selective apparatus to its normal toration is accomplished, preferably, by the flow of a current controlled from the central station over both limbs of the metallic line to which the substation apparatus has been concondition. This res-- nected in-bridge during the building-up proc-;

ess. The actuation of the switches at sub stations is accomplished by thepower stored upon the closure of in suitable mechanism circuit through actuating electromagnets.

The actuation of the switches is thus made to occur wholly upon the cessation of the flow of the current impulse through the electromagnets. v It is desirable that the control of the selective apparatus employed be from'the central station, which necessitates the provision of apparatus at the central station capable of sending currentimpulses of either'polarity over the series ground-return setting-up circuit'. tral-station apparatus be capable of causing a battery-current to flow over the two metallic limbs of the line to restore the selective apparatus. As is common to other telephone systems, the central-station equipment must also include cord connecting apparatus for. connecting subscribers who desire conversa-' tion with each other and line-signaling apparatus by which the. subscriber may notify central that he desires a connection. party-line telephone system also includes means whereby a subscriber may, when the party-line is not in use, connect his own instrument in bridge thereof in order to con verse'with the central operator or other'sub- This featurerequires the provision of means at the central station for sending current through certain electromagnetic devices of the selective apparatus which actuate the switching mechanism which controls struments in circuit.

It is further'necessarythat the cen- Our present invention relates particularly central-station equipment adaptedespe- V cially for connection with our said party-line 'system and which central-station equipment is well adapted to render automatic many of the otherwise manually-controlled operaing a preferred em odiment of the centralstation equipment, and Fig. 2 is a diagram* matic view illustrating a party-line adapted for use in-connection with the said centralstation e uipment.

In bot figures like reference characters are used to designate similar pa is.

It will be necessary for a complete understanding of our present invention to describe in general the selective party-line and its associated devices which may be used in connection with the central-station equipment which is the subject of our present invention.

Referring moreparticularly to Fig. 2, it will be seen that we have provided a metallic line a, whose'continuity is normally broken ateach of the substations through which said I is connected in parallel.

We also provide a second metallic line b, which is'preferabl continuous through all the substations an to which it At each of' the substations is provided an electroma net 1, normally connected with ground G, t e remaining terminal of which is desirably connected in series through the electromagnet 2 with the contact 3, which normall makes connection with the switch 4 to the inc-wire a. An electromagnet 5 is also provided, having a line passes.

- permanent connection with the line-wire b,

whose other terminal 6 is adapted to make contact with the switch 4 in its alternative position. Telephone or other signaling apparatus 7 is provided with a normal connection with the line b, the remaining connection through the condenser 8 being normally open between the contact 9 and the switch 10, which is connected with the line-wire a. A terminal 11', normally in contact with the switch 4,.is provided with a connection which may be closed through the key 12 with the connection to the line-wire b. Contact 13 when engaged by the switch] 4 closes the loop circuit through the substation at which it is located. The metallic limbs of the line are connected at the central station with a spring-jack in the usual'manner, the linewire a-being connected with the tip-spring 14, While the line b is connected with jackspring 15. A circuit is normally closed between the sprin 15 and the ground G through the linerop 16 and the battery 17. The mechanism of the electromagnets 1 and 5 is operated by a current flowing through the corresponding electromagnets in either direction, while a current in order to ell'ect an erases actuation of. the mechanism connected with the electromagnet 2 must be of a certain p0.- larity-that is to say, in one given direction. As previously stated, it should be remembered that Fig. 2 is merely a diagrammatic representation of the circuit arrangements and that the switches 4 and 10 are not directly actuated upon the energization of the electromagnetsfbut that these electromagnets control mechanism adapted to cause ac: tuation of the switches only upon the cessation of the flow of the current through the electromagnets.

In general the o eration of our system may be described as fol ows: A subscriber-say at substation 201desiring connection by the central operator with some other subscriber closes his key 12, thereupon closing acircuit, which may be traced as follows: from the b wire to the key 12, the contact 11, the switch 4, the contact 3, to electromagnet 2, to magnet 1, and to ground G. As will be hereinafter more fully described, there is provided at the central station a battery 17, one of whose terminals is grounded and the other of whose terminalsis normally connected with the linewire I). This battery is connected in such a direction that its current flowing through the electromagnet 2 will cause an actuation of the switch 10 on account of its polarization 5 and switch 4 will be actuated by the electromagnet 1, whereupon the circuit just traced from contact 11 to contact 3 will be broken and the contacts 6 and 13 connected with the switch 4. Thus the break in the loop-wire a is built up through the station 201 the ground connection G, is removed, and a connection is established between the a wire, through the switch 4, the contact 6, andthe electromagnet 5, with the line wire I); also, on account of the actuation of the switch 10 terminal 9 of the .telephone instrument 7 will be connected with the line-wire a, thereby placing the telehone set in bridge across the metallic lines. 11 order that the remaining substations upon a given partyline may have their ground connections thrown ofi and the series wire built up through the said stations, it is necessary that a number of impulses be sent from the central station through the line-wire a and the successive substationsiand the ground return-circuit. Such an impulse, affecting the instruments atsubstations 202, may be traced from central stations as follows: from the line-wire a at the central station to the switch 4 at substation 201, to contact 13 at the same substation, through the line-wire a to the switch 4 at substation 202, to contact through electromagnet 2, through electromagnet 1, tothc' ground G, and thus to the central station; These impulses I will normally be sent in a direction such that the switches 10 will not be actuated. If the central operator desires to call a given substation upon a party-line, the impulses sent from I lattention. of the central-station operator.

out the various opera the use of our system.

' traced from the suilicientlyto actuate the switch '4'. However,

b, which will restore all the selective apparasignal 16, whereupon the target 23 is rethe central station between the a wire and ground must be all in a normal direction which will not actuate the switches 10, ex cept that the impulse or impulses corresponding with the number or numbers of those substations which are to be connected with the line must be sent in a reverse direction'in order to actuate the corresponding switches 10, thereby placing the desired telephone instruments in bridge of the'metallic line. Upon the completion of the conversation between the subscribers it is necessa that batterycurrent be sent over the meta lic'limbs a and tus toits normal condition. This restoration is accomplished because, it will be re niembered, the electromagnets 5 have previously been bridged across" the metallic lines during'the building-up process, and an energization of these electromagnets returns the switch 4 to its normal position, at the same time breaking thecontact between switch and contact 9. In our said other-application we have described manually-operated central-station devices "designed. to accomplish the proper building up and restoration of the partiy-llne, also means for selecting any desire station or stations for conversational purposes. Our present invention contemplates automatic central-station devices such that the building-up and restoring processes may be carried on without the direct ur 1mproved.central station equipment may perhaps be best described by tracing the various circuits employed in carrying tions connected with Taking first the'condition under which a subscriberfor instance, at substation 202-calls central, it will be remembered that the subscriber closes his switch 12, whereupon a circuit may be ground G at-t-he substation through the electrornagnets 1 and 2 and the contact 3 and switch 4 to contact 11, through switch 12, which the su wire 6, to sleeve-spring oftheispring-jaok at the central station, to-contact18, to linesignal 16, to relay-spring 20, to contact 21, through battery 17, to groundG. The polarity of this battery 17 is such that current there from will actuate the various mechanisms: connected with electromagnet 2,' to actuate the switch 10 at substation. which the subscriber has close-d'jcircuitby means of his switch 12. Also' the electroriraignet 1 may or may not have'b'ee'n energized the current is suilicient to actuate the lineleased to make contact'with the *terminal 24 of the relay-coil 2'5. closed through the rel battery 26, whereup attracted, breaking Thus a local circuit is ay-coil25 and the local on the armature 27 its a 'momentary circuit-l5 thereof is rather slo bscriberclosed, to line- Y .202; through traced: as

a, to tip-spring 14, t

which has been established through the spring and contact 21 and which, it will be rememberedflvas the current which actuated the subscribers switch 10. Furthermore, the energization of the relay causes a closure of the circuit between the spring 28 and contact 29 and between the spring 30 andthe contact 31. It might be noted here-that the armature 27 and its associated spring-contacts are controlled by the target 23. Starting at contact 31, a circuit may be traced as follows: through the conductor 32 to set-up relay 33, to electromagnet-coils 34 of the vibrator 35, to contact 36, throu h themercury 37 to contact 38, through con uctor 39 to spring 40' of the pole-changing switch 41, to negative pole of battery 42 from the positive pole of the battery 42, through conductor 43, to contact 44, to spring 45, to conductor 46,to spring 30, back to contact 31.

Itmay be desirable here to point out the essential features in the operation of the vibrator 35. It consists of a horseshoeelectromagnet 47,,l1aving coils 34, betweenthe poles of which electromagnet'is pivotally mounted the armature 48. Rotatably mounted with the armature 48 is an exhausted tube 49, containing'a small quantity of mercury 37, into which tube are sealed the two contacts 36 and 38. The normal positions of the armature and mercury-tube are such that thereis an electrical connection between the con-' tacts 36 and 38 through the mercury 37 Upon the energization of the electromagnet the armature is turned suiliciently to break' the circuit between the contacts 36 and 38. This of course breaks the circuit traced through the electromagnet-coi upon become deenergized and allow the armature to swing back into its normal posi tion. The weight and inertia of the armature is such that the period of oscillation w-for example, the vibrator may close and open its circuit once in a second. Thus upon the attraction of the armature 27 an electric circuit may be traced through the set-up relay 33 and the vibrator 35, which vibrator will at once begin to open and close the said electric circuit.

course will cause the attraction of the armature 50 of the set-uprelay 33 a number of :times corresponding with thenumber of os-.

ioillations' of the vibrator-armature. This armature 50 controls a circuit which may he follows: from the armature 50 to contact 5'1', t'o'-lamp-relay 52, to ground G at the central station 'to ground at the first substation 201, through electromagnets' 1 to switch 4, to line-wire. o tip-contact 53, to'relay contact-switch 28, to contact 29, to spring 54, to contact 55, tospring 45, to contact 44, through conductor 43 to positive battery and 2 to contact 3,

-42, to contact 56; to spring 40, throughconductor 57, toarmature 50. Thus upon the ls, which there I This of closure of a subscribers switch 12 the vibrator 35 is set in" operation, which in turn sets in vibration the armature 50, which in turn controls a series of electrical impulses sent out between the line-wire wand ground. Since the line-wire c is normally broken at each of the substations, the first impulse can actuate the selective mechanism only at the first substation upon the line; but the actuation of the apparatus at this substation builds up the series line a to the second substation, whereu on-each succeedin impulse sent between t e line-wire a an ground builds up the break in the line a at a corres ondin substation. At the same time that t e brea in the loop at anyone substation is connected the groundconnection at that substation is broken. Thus each successive impulse has but one ath of travel through but one substation. he selective apparatus at the substations is so constructed that a circuit changethat is, the actuation of the switch 4 itselfoccurs only upon'the cessation of the current-flew, except that the electro magnet 2 operates switch 10, controlled thereby, immediately upon the flow of current of proper polarity therethrough. It is immaterial what' the form of mechanical arrangement of the switching mechanism is, so long as the switching occurs upon the cessation of ourrentfiow. Thus upon a sufficient number of vibrations of the vibrator all the loops in the broken line will be built up and all the-ground connections thrown ofl. It will be remem bered that the subscriberwhd set i n motion the trend of operations thus described has closed his switch 10 to bridge his instruments across the metallic limbs of the line. It will be seen that immediately after the closure of his switch 1.2 the line 'and'selective apparatus be: ing in their normal condition, instrumentalities at the central station are set in operation to at once automatically build up the line and throw off the ground connections, the

calling subscriber 202 being connected in bridge. of the metallic line. The central-station operator receives the signal upon the drop of the target 23. It will be noticed that the electromagnet 52 controls, by means of its armature 58, the followingcircu'it through the signal-lamp 59: from positive pole of the battery 42 to contact 44, to switch-contact 45, to conductor 46, to the contact associated with the armature 58, throu h the armature 58 to' the lamp 59, through theconductor 57 to the switclrcontact 40, to contact 56, to the negative pole of the battery 42. The current through the electromagnet 52 is an intermittent one, corresponding in its eriod With the setting-up current controlled by the relay 33. The circuit, furthermorathrough the relay52 can be traced only while there remains one or more ground connections at the substations upon the party-line. Thus the lamp 59 is caused to flash intermittently while the line-wire a is being built up, and after the completion of this buildingup p1 ocess the lamp 59 will become extinguished, as the circuit through relay 52 will be broken upon. the ground connections at the substations being broken. Thus this lamp provides a signal for the operator by means of which she may ascertain whether or not the party-line has been completely built up. Therefore when the lamp has stopped flashing she may manually restore the drop-target 23, which breaks the local circuit thro ugh relay 25, thus preventing further actuation of the vibrator 35 and the relays controlled"- ringing-generator64 being provided, as usual;

After plugging into the answering-jack the operator ascertains the number of the subscriber with Whom the'calling party desires conversation and makes the connection in the usual way. The operator upon receiving a disconnect signal through her drop 62 must restore to its normal condition the party-line. This, it will be remembered, is accomplished by sending a comparatively heavy "batterycurrent across'the metallic limbs of-the line. Since the cord-circuit is connected with the lines a and b, the restoring-current is-preierably connected with the line through the cord-strands. Thus the contacts 65 and. 66, which, t will be seen, are connected with the terminals'of' the battery 42, may be brought into bridge connection withthe cord-c rcuit by'a manipulation of the key which operates springs 67 and 68, these springs beingconnected each with a strand of the cord-circuit. A second operative condition is that .in which a iven subscriber upon a party-line is to be called. Supposing that substation No. 3 on party-line 200 is to be called. In order to accomplish this,it will be necessary to send a number of impulses between the c'wire andground corresponding to the number of substations upon the party-line. The. third of these impulses must be in a reverse-direction, so as to operate the switch 10 at substation 203. The operator'inserts her calling-plug 61 between the jack-springs 14 and 15,,in-

serts the selector-plug .69 in No. 3 of theselector-jaoks70. She then'depresses asingle key, spreading the springs 71 and 72 and 73 and 74. The depression of spring .74 breaks a connection through the tip-strand with the answcringlug 60,-wh lethe raisingof the, s )ring. 71 sleeve-strand from the plug 60. The movement of these springs also establishes other circuits, which will be hereinafter traced. A

reaks the connection with the IIS - depressioh of the spring 72 causes a connec- 45, through conductor 46 to'conductor 76, to"

spring 72. Thus an interm ttent pulsating current is setup through the agency of the vibrator,

I by set-up relay 33, causes intermittent pulsating currents to be sent from negative battery to ground G, while positive battery is connected to the a wire through the tip-strandof the cord-circuit. This circuit may be traced fromthe spring 71, connected with the tipstrand, to the contact 77,- to conductor 76,

which, it will be remembered, is connected di rectly to the positive battery. As previously d scribed, the flashing of the lamp 59 will indicate the progress of the buildin -up process.

It will be remembered that in order to connect the substation 203 across the metallic lines a and b it is necessary that the third of the setting-up impulses be in a reverse direction. The armature 78 of the pole-changing switch 79 controls the springs 40, 45, and 54 and is actuated by the energization of the electromagnet 80. Therefore in order to reverse the direction of one of the setting-up impulsesfor instance, the thirdit will be necessary to cause the .energization of the electromagnet 80, which of course, through the pole-changing switch 79, will reverse the connection of the battery 42 with the settingup circuit. To accomplish this proper reversal of the current, counting 'mechanism81 is provided. It will be seen that the tipsprings of the selector-jacks are connected each with a contact-button-82 of the counting device. A rotatably-n ounted switch 83 is adapted to be stepped around so as to make contact successively with the buttons 82. The step-by -.step operation. of the switch-arm 83 is accomplished by means of a ratchet-wheel 84, actuated by a pawl 85, carried upon a lever 86, which is actuated upon the energization of the electromagnet 87. The circuit for the electromagnet 87 may be traced as follows: Upon the manipulationof the spring 73 contact is made with the contact 88, from which circuit ma be traced through the conductors 76 and 46 to the spring 42, from negative battery to contact 56, .to spring 40', through conductor 39, to contact 38, through the mercury 37, to contact 36, to conductor 89, to electromagnet 87, through conductor 90, to spring 73. It will'be seen that this circuit is interrupted b the breaking of the circuit within the vi rator-tube, which, it will-be remembered, has been set in operation. Thus as each setting-up impulse is sent out over thcline theelectromagnet 87 while the armature '50, controlled 45, to contact 44, to positive battery .in of the lamp will be energized to attract its armature mounted upon the lever 86, thereby withdrawing the pawl 85 back ever one tooth of the ratchet-wheel 84. Upon the denergization of the magnet 87 when the current is interrupted by the vibrator the counterweight 91 upon the lever 86 causes a reverse movement of the pawl 85, which moves the switcharm 83 into contact with the succeeding button 82. Thus the first setting-up impulse moves the switch 83 into contact with the second button, which is connected with the tipvspring of the second selector-jack. Similarly the second setting-up impulse moves the switch-arm 83 into contact with the third button, which is connected with the tipsprin of the third selector-jack, 'into which, it wil .be remembered, the selector-plug 69 has been inserted, so that a connection is formed between the selector-plug 69 and the switch-arm 83 immediately upon the cessaA tion of the flow of the second setting-up impulse. Thus after the cessation of the second settingup impulse a circuit may be traced as follows: from the switch-arm 83, through the conductor 92, connected there with, to the electromagnet 80, to .positive battery 42, from negative battery 42, through conductor 93, to selector-plug 69, to the tipspring'of N o. 3 selectonjaek, to the N o. 3'

contact-button, back to the switch-arm 83 Thus a circuit is closed which energizes the electromagnet 80, thereupon actuating the pole-changing switch 79. ing actuation of the armature 50, controlling the setting-up currents, will cause the settin -up current to flow betweenthe a wire Thus the succecdan ground'in a reverse direction, which direction must be such as to cause the-proper energization of the electromagnet 2 at substation 203 to'actuate the polarized switch 10 to connect the subscribers instruments in bridge of the metallic telephone-lines a, and b.

Upon the cessation of the flow of this re versed setting-up impulse the switch-arni 83 will move on to the fourth button, thereupon breaking circuit through the electromagnet 80, whereupon the retractile spring will cause the pole-changing switch to resume its nor mal condition. Thus the getting-up impulse corresponding with the number of the su scriber to be called upon a party-line will be automatically reversed in direction without the immediate care and attention of the operator. As previously pointed out, thcdiasih- 59 will indicate that the: line is eingbuilt up, and when the lashing-ceases the operatorniay release the springs Z1 and 72 and 73 and 74, thereupon permitting conversation between the connected subscribers through the cord-circuit. Any desired subscriber may be connected into circuit by the insertion of the selector-plug in'the proper selector-jack. Upon receiving a disconnectsignal the operator may restore the partyed with springs 67 and 68, as heretofore pointed out.

The counting mechanism 81 will have its switch-arm 83 stepped around a number of spaces corresponding with the number of energizations of the electromagnet 87. A clockspring 94 is desirably provided, which upon t e release of the pawl 85 and thedetentpawl 95 causes the ratchet-wheel and switcharm to be swung back against the stop 96. An electromagnet 97 is provided for the purose of actuating the armature-lever 98 to reease the pawls 85 and 95. This restoration of the counting mechanism is accomplished by a circuit which may be traced from negative battery 42 through the conductor 93 to the tip of the plug 69, which when being removed from any one of the acks makes a momentary contact with the long jack-spring thereof, whereupon circuit may be traced through the said spring and the conductor 99' to the electromagnet 97, to positive battery 42. Thus this momentary current actuates the lever 98 to release the pawls and allow the ratchet-wheel and switch to return to their normal position. If for any reasonthe momentary current flowing through the restoring-electromagnet falis to properly restore the counting mechanism, the operator makes another restoring-circuit by a momentary contact between the selector-plug and the long spring of the selector-jack when she inserts the selector-plug into the j ack'-'that is,

' the operator has what may be termed a double certainty of properlyrestoring the counting mechanism, once when she removes a selector-plug from the jack and again when she inserts a selector-plug in order to call another subscriber.

Each operators position maybe desirably provided with two or'more plugs connected in parallel with the selector-plug 69, whereby, for instance, the'insertion of two plugs within two'oi the selector-j acks 70 will cause a reversed setting-up impulse to be sent through two substations, whereupon the telephone instruments at these two substations will be connected in bridge of the telephone-lines. This is necessary in case a subscriber .on any one party line desires conversation with another subscriber on the same party-line. The calling subscriber will get central invthe usualtmanne'r, whereupon the partyiine .will be automatically set up, as arerrir'rusly described. Uponmaking it known the central operator that cOnnecti n-isd'esired with another subscriber upon the same party-line the operator first restores the selective a pa ratus on the party-line by a depression 0 the key controlling the springs '67 and 68 and thereafter places selector-plugs in the jacks corresponding with the two subscribers desiring conversation, whereupon the line is again set up,but with twosetting -'.up im erases pulses properly reversed to connect in the two desired substations.

One of the above-described automatic settin -up equipments is desirably provided for eac operator's position. Since such an operators position may desirably be connected with a number of party-lines, it frequently happens that a subscriber may be calling at the samev time another party-lineis'. being set up.-

As heretofore pointed out, the setting-up impulses Which are automatically caused to fiow when the subsizriber closes his switch 12 should all be in one direction, and this direction should be the normal-one, so that'none of the switches 10 at any of the'substations will be actuated by the setting-up impulses sent out from the central station; but when an operator is calling a subscriber on a partyline at least one of the setting-up impulses should flowin the reverse direction in order to connect in the called subscriber. This reversal of current is effected by the poleohanging switch41, due to the energization of the electromagnet 80. Since this actuation of the pole-changing switch reverses the battery connection with the circuits associated therewith, the natural result would be that a reverse current could be sent out over both the party-line on which the calling-substation was located and that on whieh'the called substation was located. This of course would cause an improper building up of the calling party-line, the reverse current serving to connect in a substation which should have no connection across metallic lines a and b. To obviate this improper setting up of the calling-line which would result from the improper reversal of the setting-up current, we

ave provided the switch 54, which is normally in connection with the contact 55. The automatic setting-up current normally passes through this connection; but upon the energization of the coil the pole-changing switch is actuated, and since the spring 54 is controlled by the same armature 78 this normal connection is broken, whereupon no setting-up impulse is'sent over the calling-line at the time at which a reversed current is automatically sent over the called line. Thus while the calling-line misses one of the settingupimpu-lses, which would normally have been sent out over the same, all of the impulses which are sent out over this line-are in the proper direction and no false actuation of the instrumentalities on the calling party-line is caused by the reversal of the battery connections necessary to the proper setting up of the called line. r

In practice we find it desirable to mount the vibrator, counting mechanism, polechanger, andthe set-up and lamp relays all upon one base-board provided with terminalposts, from which may be" run the conductors leading to the selector-jacks, the switching devices controlling the operation of the dedrop 16, it will be ap arent to those skilled vices mounted on the said base-board and the conductors through which impulses-are sent. It will be seen that the invention provides automatic setting-up devices for use at a central station in connection with a great variety of party-line telephone systems.

While we have particularly described our invention-as adapted for employment with a particular party-line system, it is not to be understood that the present invention is limited to application to this system alone.

Our invention provides means whereby a party-line is entirely set up and the calling subscriber properly connected therewith without any care or attention from the central-station operator whatever, it being merely necessary that the operator upen re ceiving a proper signalsuch, for instance, as that given by the lamp 59-plug into the proper answering-jack and thereafter communicate with the calling. subscriber in exactly the same way as she would with a subscriber connectedwith a single metallic line.

While we have shown a manually-restored 4 to contact 11, and

in the art that any se f-restoring drop might be substituted therefor.

Particular advantages are gained by the use f our improved central-station equipment due to the feature which wemay term the instantaneous lockout. It will be seen that immediately upon one subscriber closing his switch 12 the drop-target 23 is released, thus closing a local circuit through the relay-coil 25,- whereupon the armature 27 is attracted and the current from battery 17, flowing between contact 21 and spring 20, is interrupted. Since it is necessary for any other subscriber in order to bridge his telephone instruments across the a and 6 wires to obtain battery-current from the battery 17 through a connection between the contact 21 and switch 20, this second subscriber cannot connect in his instruments after this con- I nection has been broken. Thus 'when the first calling subscriber breaks this connection upon depressing his switch 12 all the remaining substations on the same party-line are instantly and eflectually' locked out. It might occasionally happen that a subscriber on a party-line would wish to obtain connection with the central station during the time at which the line was being set up from the central station; If the subscriber who thus -wished to call central was located a considerable number of substations from the central station, it is possible that as the line was set up through the nearer substations a sufficient amount of current could pass through the restoring-electromagnets which were bridged between the a and 1) wires to allow a current to flow through the 1) wire sufficient to actuate the switching mechanism at the more remote station. The circuit then at this more remote station at which a would-be calling l .each operators position.

subscriber had closed his switch'12 would be from the ground through the electromagnets 1 and 2 to the contact 3, through the switch through the then closed switch 12 to the bwire. Thus a circuit would be established through which a current might flow to actuate the switch. 4; but, it will be remembered, the normal setting-up impulses are in such a direction that the switch 10 at this more remote station would not be actuated. Hence'the second subscribers instruments would not be connected across the line. Our system presents another advantage over the central station arrangements heretofore used for selecting subscribers on a party-line in the great simplicity of the meansemployed plug in the proper selecting-jack. This is a 1 great advance over those systems in which the operator must insert pins in a switch-dial or otherwise manipulate contact-points therein and then, for instance, actuate a springmotor mechanism adapted to operate proper switching or pole-changing mechanism. Such systems of the prior art, furtlnrmore, require a number of operations by the central-station operator in properly restoring both the line mechanism and the central-station mechanism. Our invention, it will be seen, provides for the complete restoration of the party-line by the manipulation of a single key on the operators board, and the mere removal of the selector-plug from the selecting-jack restores the central-station mechanism to its normal condition. Of course the cord-circuit plugs must be removed from their jacks, as in any other telephone system.

In the case of a calling-station located on a party -line our invention provides means whereby there is required of anoperator only one operation in addition to those necessary in any simple telephone-exchange board, and in case the called station is located on apirrtyline only three additional operations will be required. In the first case the'one additional operation consists in a manipulation of the restoring-key controlling the springs 67 and 68, and in the second case the additional op; erations consist, first, in placing the selectorplug in a proper selector-jack, second, in manipulating the key controlling the springs 71 and 72 and 7 8 and 7 4, and, third, in manipulating therestoring-key, as in the first case. The only space required by the instrumentalities einployed in our system in addition. to that required in any exchange-board is the small space occupied by the restoring-keys and the setting-up keys, one of each'tor each cord-circuit, and a bank of selector-jacks for The number of se lector-jacks should be at least as great as the largest. mu 'iber of substations on any one party-line connected with that position.

While we have herein shown and particularly described one preferred embodiment of our invention, it will be apparent to those skilled in the art that many modifications therein might be incorporated without de parting from'the spirit of our invention. WVe therefore do not WlSll to limit ourselves to the precise disclosure herein set forth; but,

Having described our invention, we claim as new and desire to secure by Letters Patent 1. In a selective partyline system, the combination with the central station, of lines runningtherefrom to a series of substations,

signaling apparatus at each ofsaid substations norma y disconnected from said lines, means at each substation absolutely controlled from the central station, and from the said substation, whereby the corresponding signaling apparatus may be connected with said lines, and means whereby an actuation of said first means controlled from the corre sponding substation, establishes a condition such that the substation control at the other substations of the said first means is rendered ineffective, substantially as described.

2. In a selective party; line system, the combination with the central station of lines running therefrom to a series of substations, signaling aparatus at each of said substations, norma ly disconnected from said partylines, means primarily controlledfrom the central station, and secondarily controlled from each substation, whereby the corresponding signaling apparatus may be connected with said lines and means whereby an actuation of said first means controlled from any one substation, establishes a condition such that the substation control at the other substations of said first means is rendered ineffective, substantially as described.

3. In a selective partyline system, the combination with a central station, of lines running therefrom to a series of substations, signaling ap aratus at each of said substations normal y operatively disconnected from said lines, means controlled from the central station whereby any of the signaling apparatus may be operatively connected with the said lines, said means being subject to a secondary control from each substation, the control exercised from any one substation serving secondarily to govern the operative connection of the signalin apparatus at the same substation with saic lines, and means whereby an actuation of said first means due to the control exercised from any one substation establishes a condition such that the subr station control at the other substations of the said first means is rendered ineliective,substantially as described.

4. In 'a selective party-line system, the combination with a central station, of lines running therefrom to a series of substations; signaling apparatus at each of said substa- 'means whereb tions normally operatively disconnected from the said lines, means primarily controlled from the central station whereby the signaling apparatus at any substation may be o.peratively connected with the lines and secondarily controlled from each substation, the control exercised from any one substation serving secondarily to govern the operative connection of the signaling apparatus at the same substation with said lines, and means whereby an actuation of said first means due to the control exercised from the central station establishes a condition such that the substation control at the other substations of said first means is rendered ineffective, substantially as described.

5. In a selective party-line system, the combination with a central station, of lines running therefrom to a series of substations, signaling a'p aratusat each of said substations norma ly operatively disconnected from said lines, means primarily controlled from the .central station whereby the signaling apparatus at any substation may be operatively connected with said lines and secondarily controlled from each substation, the control exercised from any one substation serving secondarilyto govern the operative connection of the signaling apparatus at the same substationwith said lines, and means whereby an actuation of said first means due I is rendered ineffective, substantially as described.

6.. In a selective party-line system, the combination with a central station, of lines running from the central station to a series of substations, one of said lines being normally 'broken' at each substation, signaling apparatus at each substation normally disconnected from said broken line, means controlled from each substation whereby the corresponding signaling apparatus may be connected with the broken line, and means set in operation by an actuationof said first the said broken line is built up, substantia ly as described.

7. In a selective party-line system, the combination with a central station, of lines running from the central station to a series of substations, one of said lines being normally broken at each substation, signaling apparatus at each substation normally disconnected from said broken line, means primarily controlled from the central station whereby any substation signaling apparatus may be connected with the broken line and secondarily controlled from each substation whereby the corresponding signaling appa ratus may be connected with the broken line, and means automatically set in operation by an actuation'of said first means,

a mles 1;stamps;

whereby the sai stantially as describedQ substations, one of said lines being'n'ormally broken at each substation,"signaling appa ratus at each substation normally'disconnected from said broken line, means controlled from each substation whereby. the.

corresponding signaling apparatus maybe ondarily connected with said brokenline, and means whereby an actuation ofsaid first means controlled from any one substation establishes a condition such that the substation control at the other substations of the said first means is rendered ineffective, substantially as described.

9. In a selective party-line system, the combination with a central station, of lines running from the central station to a series of substations, one of said lines being normally broken at each substation, signaling apparatus at each substation normally disconnected from said broken line, means controlled trom the central station whereby anyof the signaling apparatus may be connected with said broken line, said means being seccontrolled from each substation, whereby the corresponding signaling apparatus may be connected with said lines, and means whereb an actuation of said first means due to tile control exercised from any one substation establishes a, condition such that the -substation control at the other substations of the said first means is rendered ineffective, substantially as described.

- 10. In a selective party-line system, the combination-with a central station, of lines running from the central station to a series of substations, one of said lines being normally broken at each substation, signaling apparatus at each substation normally dis-, connected-from said broken line, means primarily controlled from the central station whereby the signaling apparatus atany substation may be connected with the broken line, andsecondarily controlled from each substation, whereby the corresponding signaling apparatusmay be connected with said broken line, and means whereby an actuation of said first means due to a control eX- ercised from the central station establishes a condition such that the substation .control at the other substations of said first means isrendered ineffective, .substantially as described.

11. In a selective party line system, the combination with 'acentral-station, of lines running from the central station to a series of substations, one of said lines beingnormally broken at each substation,- signaling apparatus at each'substation normally disconnectedfro'm said broken line, means primarily controlled from the central station combination with a central station, 5 er adapted to means whereby the substation control of the whereby atany sub -n I substation, whereby,the corresponding sig- :70. said line, and meanswherebyi'an ac I turation of said; first means due to acontrol naling apparatus ,maybe connected with exercised either from central or from any one running from the central stationto a ,-.series-v tion and tral station, adapted line automatically, scribed.

to buildup .said broken running from the central stationto-aseries substation establishes a conditionsuch that Ithe substation control atthe other substa-M tions of the saidfirst means isrendered inefl fective,substantially asf described 12, Inja selectiveparty-line .system the combination with a central station, got-lines,

of substations, one ofsaid lines ;bei1 1g' nor-f mally broken at each substation andmeans I secondarily controlled from anyone substaprimarily set in operation at the cenu stant ly .d y

of substations, one of said lines beingnor-y mally broken at each substation, and means primarily controlled and secondarily controlled from any substa tion, adapted to build up said br ken line automatically, substantial y as described;

from 'thel'central station; a

14. In a selective party-line system, the

combination with a central station, of lines running from the central station to a'series of substations, one of the lines being; normally broken trolled and set in operation at the ce lal staat each substation, means 0011- I tion adapted to build up said broken line au tomatically, trolling said first means from each of said substations, substantially as described.

15, In a selective combination with a running therefrom to a series of substations,

one of said lines being normally' brokenat and means for secondarilyconl i party-linel'isyste m, central station, of lines cause the actuation of said line-signal, and

means set in operation by the actuationot said line-signal adapted to build upflsaid broken line, substantially asdescribed.

16. In a selective .party-line s'ys the fcatedateach substation adapted to cause lines the actuation of said line-signal,-means s'et'in" operation by the actuation of said. line-signal" build up saidbroken .line,*and

line-signal is rendered ineffective upon connection of said cord-circuit with said lines, substantially as described.

17. In a selective party-line system, thecombination with the central station, of lines running therefrom to a series of substations, one of sald llnes being normally broken at each of said substations, a line-signal associated with the said lines at the central station,

I central station adapted for connection with said lines, 'a line-signal associated with the.

lines at the central station, means located at each substation adapted to cause the actuation of said line-signal, means set in operation by the actuation of said line-signal but primarily controlled from the said central station, whereby the broken line is automatically built u and means whereby the substation contro of the line-signal is rendered ineflective upon the connection of said cordcircuit with said lines, substantially as described.

19.. In a selective party-line system, the combination with the central station of lines running therefrom to a series of substations, one of said lines being normallybroken at each substation, a cord-circuit at the central station adapted for connection with said lines, a line-signal associated with the lines at the central station, means located at each substation ada ted to cause the actuation of said line-signa, means set in operation by the actuation of said line-signal, but primarily controlled from said central station, whereby the broken line is automatically built up, and means whereby the substation control of said line-signal is rendered ineiiective upon an actuation of the said line-signal caused from any one substation ,substantially as described.

20. In combination, a source of electric current, a pole-changing switch associated therewith, an electromagnet adapted to actuate said pole-chan 'ng switch, switching means adapted to ma e connection with successive contacts, electromagnetic mechanism adapted to-cause the step-by-step shifting of said switching means to successive contacts, and an electric circuit including the-source of current, the switching means and the electromagnet adapted to actuate the pole-changing switch, saidcircuit being adapted to be completed through any predetermined contact, whereby the e'lectromagnet will be energized to actuate the pole-changing switch upon a predetermined step of the switching means, substantially as described.

- 21. In combination,a source of electric current, a pole-changing switch associatedtherewith, an electromagnet adapted to actwate said pole-changing switch, switching means ed to cause a one-step shifting of said switching means to a successive contact upon a cessation of current-flow therethrough, a periodically-interru ted electric current flowing through sai electromagnetic mechanism, whereby a stepbystep shifting of said switching means is caused, and an electric circuit including the source of current, the switching means and the electromagnet ada ted to actuate the pole-changing switch, said circuit being adapted to be completed through any predetermined contact, whereby the electromagnet will-be energized to actuate the pole-changing switch upon a predetermined step of the switching means, sub stantially as described.

22. In combination, a sourceof electric cur rent, a pole-changing switch associated therewith, an electromagnet adapted to actuate said pole-chan ing switch, switching means adapted to ma e connection'with successive contacts, an electromagnet adapted to cause the one-step shifting of said switching means to a successive contact upon a cessation of current-flow therethrough, means adapted'to cause a periodically-interrupted current to flow through said eleotromagnet, and an electric circuit including the source of current, the switching means and the electromagnet adapted to actuate the pole-changing switch, said circuit being adapted to be completed through any predetermined contact, whereby 7 adapted to make connection with successive contacts, electromagnetic mechanism adapt-' the electromagnet will be energized toactuate the pole-changing switch upon a predetermined ste of the switching means, substantially as escribed.

23. In combination, a source of electric current, a pole-changing switch associated there with, an electromagnet adapted to actuate said pole-changing switch, switching means adapted to make connection with successive contacts, an electromagnr-it adapted to cause the one-step shifting of said switching means upon a cessation of current-ilow therethrough, means controlled from the central station adapted to cause a periodically-interrupte .l current to flow through said electromagnet,

and an electric circuit including the source of current, the switching means and the electromagnet adapted to actuate the polechanging switch, said circuit being adapted to be completed through any predetermined contact, whereby the electromagnet will be energized to actuate the pole-changing switch upon a predetermined step of the switching means, substantially as described.

24. In combination, a source of electric current, a pole-changing switch associated therewith,an electromagnet adapted to actuate said pcle-chan ing switch, switching means adapted to ma e connection with successive contacts, electromagnetic mechanism adapted to cause the step-by-step shifting of said switching means to successive contacts, an electric circuit including the source of current, the switching means and the electromagnet adapted to actuate the pole+changing switch, a selector-jack connected with each of said contacts, and a selector-plug adapted for insertion within any of saidjacks, thereby completing said electric circuit through any predetermined contact, whereby the electromagnet will be energized to actuate the pole-changing switch upon a predetermined step of the switching means, substantially as described.

25. In combination, a source of electric current, a pole-changing switch associated therewith, an electromagnet adapted to actuate said. pole-changing switch. switching means adapted to make connection with successive contacts, electromagnetic mechanism adapted to cause the step-by-step shifting of said switching means to successive contacts, an electric circuit including thesource of current, the switching means and the electromagnet adapted to actuate, the pole-changing switch, a selector-jack connected with each of said contacts, a selector-plug adapted for insertion within any of said jacks, thereby completing said electric circuit through any predetermined contact whereby the electromagnet will be energized to actuate the pole changing switch upon a predetermined step of the switching means, and means whereby the insertion of the selector-plug within any selector-jack will cause the restoration of the switching means to its normal condition, substantially as described.

26. In combination, a source of electric current, a pole-changing switch associated therewith, an clectromagnct adapted to actuate said pole-changing switch, switching means adapted to make connection with successive coin/acts, electromagnetic mechanism adapt- .cd to cause the stepby-step shifting of said switching means to successive contacts, an electric circuit including the source of current, the switching means and the electromagnet adapted to actuate the pole-changing switch, a selector-jack connected with each ol said contacts, a selector-plug adapted for insertion within any of said jacks, thereby completing said electric circuit through any predeterminedcontact, whereby the electromagnct will be energized to actuate the polechanging switch upon a predetermined step of the switching means, and means whereby the rcmovalof the SelectW-plug from any selector-jack will cause the restoration of the switching means to its normal condition, substantially as described.

27. In combination, a source of electric current, a pole-changing switch associated therewith, an electromagnet adapted to actuate said pole-chan ing switch, switching means adapted to ma e connection with successive contacts, electromagnetic mechanism adapted to cause the step-by-step shifting of said switching means to successive contacts, an electric circuit including the source of current, the switching means and the electromagnet adapted to actuate the pole-changingswitch, means adapted to close or break said circuit through any predetermined contact, and means whereby the actuation of said means to close said circuit causes a restoration of said switching means to its normal condition, substantially as described.

28. In combination, asource of electric current, a pole-changing switch associated therewith, an electromagnet adapted to actuate said pole-chan ing switch, switching means adapted to ma e connectionwith successive contacts, electromagnetic mechanism adapted to cause the step-by-step shifting of said switching means to successive contacts, an electric circuit including the source of cur- 'rent, the switching means and the electro- .electric circuit including the source' of current, the switching means and the electromagnet adapted to actuate the pole-changing switch, a selector-jack connected with each of said contacts, a selector-plug adapted for inserti-on'withiii' any of said jacks, thereby completing said electric circuit throu h any predetermined contact, whereby the (ilectromagnet will be energized to actuate the polechanging switch upon a predetermined step of the switching means, and an auxiliary con- ,tactin each of said selector-jacks adapted to make momentary contact with said selectorplug upon 1nsert1on in or'removal from said jack, said con-tact being adapted to close an electric circuit through electromagnetic.

mechanism adapted to cause the restoration of said switching means to its normal condition, substantially as described.

30. In combination, a source of electric our- 1 ii in from said source to be intermittent, means for reversing the connection of the first of said'circuits with said source of currents, and means adapted to disconnect'the second circuit from said source during the reversal of the connection of said first circuit, substantially as described.

31. In combination, a source of electric Gurrents, two circuits electrically connected therewith, means for causing the currentfiow from said source to be intermittent, a pole-changing switch for reversing the connection of the first of said circuits with said source of currents, and means adapted to disonnect the second circuit from said source during reversal of the connection of said first circuit, substantially as described.

32. In a selective party-line system, the combination with a central station of three lines running therefrom to a series of substations, signaling apparatus at each of said substations normally operatively disconnected from said" lines, means at each substation ab solutely controlled from the central station and secondarily controlled from the said substation, whereb the corresponding signaling apparatus may e connected with two of said lines, and means whereby an actuation of said first means controlled from the corresponding substation, establishes a condition such that the substation control of the said first means is rendered ineffective, substantially as described.

33. In a selective party-line system, the combination with a central station of three lines running therefrom to a series of substations, signaling a paratus at each of said substations, normal y opcratively disconnected from said l'ines, means at each substation directly controlled from the said "substation, whereby the correspondin signaling a tus may be connected wit two of sai ines, and means whereby an actuation of said first means controlled from any substation, establishes a condition "such that the substation control of the said first means is rendered ineffective, substantially as described.

34. In a selective party-line system, the combination with a central station .of lines running from the central station to a series of substations, one of said lines being normally broken at each substation, signaling apparatus at each substation norma 1y disconnected from said broken line, means controlled from .each substation, whereby the correspo ndi1i signaling apparatus may be connected wit the broken line, and means automatically set in operation by an actuation of said first means, whereb the. said broken line is built up, substantially as described. 1

35. In. a selective party-line system, thev combination with a central station of lines running from the central station to a series of arasubstations, one of said lines being normally broken at each substation, and means controlled from any one substation and set in operation at the central station, adapted automatically to build up a non-inductive circuit through said broken line, substantially as described.

non-inductive circuit through said broken line, substantially as described.

37. In a selective party-line system, the

combination with a central station of lines running from the central station to a series of substations, one of said lines being normally broken at each substation,'me ans controlled and set in operation at the central station, adapted automatically to build up a non-inductive circuit through said broken line and means for secondarily controlling said first means from each of said substations, substantially as described.

38. In a selective signaling party-line system, the combination with a central station of lines running therefrom to a series of substations, one of said lines being normally broken at each substation, a cord-circuit at the central station adapted for connection with said lines, a line-si 'nal associated with said lines at the centra station, means located at each substation, adapted to cause the actuation of said line signal, and means whereby the substation control of the linesignal is renderedinefi'ective upon the connection of said cord-circuit with said lines, substantially as described.

39. In a selective party-line system","tlie combination with a central station, of lines running therefrom to a series of substations, one of said lines bein normally broken at each substation, a cor -'circuit at the central station adapted for connection with said lines, a line-signal associated With the lines at the central station, means located at each substation, adapted to cause the actuation of said line-si nal, whereby the broken line is automatica ly built up, and whereby the substation control. of said line-signal is rendered ineffective upon an actuation of the line-sign'al, caused by the control exercised from any one substation, substantially as described.

40. In combination a source of electric current, current-reversing means associated therewith, an electromagnet adapted to ac-- tuate said current-reversing means, switchin'g'means adapted to make connection with successive contacts, electromagnetic mechanism .adaptedto cause the step-by-step hifting of said switching means to successive I30 5 successive contacts, electromagnetic mechthe electromagnct adapted to actuate the current-reversing means, said circuit being adapted to be completed through any predetermined contact whereby the electromagnct will be energized to actuate the current-reversing means upon a predetermined step of the switching means, substantially as described.v

" 41. In' combination, a source of electric current,current reversing means associated therewith, an electromagnct adapted to actuatesaid current-reversing means, switching means adapted to make connection with anism,adapted to cause a one-step shifting of said switching means to successive contacts upon a cessation of current-flow therethrough, a periodically interrupted \electric current flowing through said electromagnetic mechanism, whereby a step-by-step shifting of said switching means is caused, and an electric circuit including the source of current, theswitching means and theelectromagnet adapted-to actuate the currentreversing means, said circuit being adapted to be conplated through any predetermined contact whereby the electroma'gnet will be energized to actuate thecurrent-reversing means upon a predeterminedstep of-the switching means, substantially as described.

42. In combination, a source of electric current, current-reversing means associated therewith, an electromagnct adapted to actuate said current-reversing means, switching means adapted to make connection with successive contacts, electromagnetic mechanism adapted to cause the step-by-step shifting of said switching means to successive contacts, an electric circuit including the source of current, the switching means and the electromagnct adapted to actuate the current-reversing means, means adapted to close or break said circuit through any prede -termined contact,' and means hereby the actuation of said means to close said circuit,

causes a restoration of said switching means to its normal condition, substantially as described.

43. In combination, a source of electric current, current-reversing means associated therewith, an electromagnct adapted to actuate said current-reversing means, switching means adapted to make connection with successive contacts, electromagnetic mechanism adapted to cause the step-by-step shifting of saidswitching means to successive contacts, an electric circuit including the source of current, the switching means and the electromagnct adapted, to actuate the current-reversing means, means'adapted to close or break said circuit through any predetermined contact, and means whereby the actuation of said means to break said circuit, causes a restoration of said switching means to its normal condition, substantially as described. r

'44. In combination, a source of electric current, current-reversing means I associated therewith, an electromagnct adapted to actuate said current-reversing means, switching means adapted to make connection with successive contacts, electromagnetic mechanism adapted to cause the step-by-step shifting of said switching means to successive contacts, an electric circuit including the source of current, the switching means and the electromagnct adapted to actuate the current-reversing means, a selector-jack connected with each of said contacts, a selectorplug adapted for insertion within any of said jacks, thereby completing said electric circuit through any-predetermined contact whereby the electromagnct will be energized to actu ate the current-reversing means upon the predetermined step of the switchingmeans, substantially as described.

In witness whereof we hereunto subscribe our names this 6th day of October, A. D. 1902.

ARTHUR F. PooLE; FRANK B. HALL.

Witnesses:

MINNIE K. CooHRAN, LANDY SISSON.- 

